The invention relates to an optical communication element for use in an optical telecommunication cable. The element comprises at least one optically conducting glass fiber bonded to a metal tape by means of an adhesive.
The invention also relates to a method of producing such an optical communication element in which the glass fiber is attached to the metal tape by means of the adhesive.
In addition, the invention relates to an apparatus for producing an optical communication element and an optical telecommunication cable.
The optical communication elements according to the invention are intended to be incorporated in optical telecommunication cables. The optically conductive fibers are incorporated in such elements before they are assembled into cables in order to strengthen the optical fibers. Furthermore, unprotected glass fibers are very susceptible to bending which causes the optical properties of the glass fibers to deteriorate considerably. In addition, glass fibers are sensitive to stress corrosion.
U.S. Pat. No. 4,138,193 describes an optical communication element which has been assembled from some optical glass fibers which have been coated with a conventional layer. The glass fibers are bonded to a metal tape by means of an adhesive. The glass fibers are covered with a polyester film. the metal tape may be wound in the form of a spiral around a core for producing an optical cable. Compared with a synthetic resin material tape the use of a metal tape has the advantage that the element is stronger and has a greater resistance to temperature changes due to the relatively low coefficient of expansion of metal. The known element is not moisture resistant since all synthetic resin materials, and consequently also the polyester cover film, are to some extent permeable to moisture.